Experimental Study of Effect of Noise and Link Distance on Infra-Red Based WBAN

Abstract

The advent of wireless body area network (WBAN) has greatly facilitated the early prevention and instant information transfer in case of critical conditions. The WBAN presently deployed mostly utilize wireless technology based on Radio Frequency, Ultra-wide band or Microwave. Due the hazardous nature of these technologies to human tissues and organs, and overcrowdings of radio frequency spectrum; an alternative using Optical communication is proposed in this paper for WBANs. Various vital sign sensors data is collected and transmitted to a central unit i.e. an Arduino microcontroller using infra-red signaling. This paper investigates and compares the results of various photo detectors to be used as receiver and different LED drive circuits as transmitter. Various experiments are performed to observe the effect of varying link distance and white noise level. The results are compared through SNR and BER for these varying parameters. Our developed system is built by using simple, inexpensive and low power components to provide a low cost solution. The link distance is tested up to 4 feet. No external optics was used yet the experiments yielded good SNR values. The results demonstrate that the developed IR system can be used successfully for WBAN as an alternate of conventionally deployed RF based WBANsover a short range.